Device and method for filtering particles from a liquid in a dishwasher

Abstract

A device is provided for filtering particles from a dishwashing fluid in a dishwashing machine, the dishwashing machine having a dishwashing container in which are disposed items to be subjected to the application of a dishwashing liquid thereto such that particles disentrained from the items during the application of a dishwashing liquid are entrained with the dishwashing liquid. The device includes a container operable to retain therein a predetermined quantity of a liquid mixed with at least one of a foam-forming substance and cleaning agents, the container including an arrangement for producing a flow of a gaseous fluid through the predetermined quantity of the liquid so as to generate a foam layer. The foam layer filters out from a dishwashing liquid passed through the foam layer a substantial fraction of particles entrained with the dishwashing liquid and such filtered-out particles are retained in the foam layer.

The invention claimed is: 
     
       1. A dishwashing machine comprising:
 a dishwashing container adapted to contain items to be subjected to the application of a dishwashing liquid thereto such that particles disentrained from the items during the application of a dishwashing liquid are entrained with the dishwashing liquid, 
 a device for filtering particles comprising: a container operable to retain therein a predetermined quantity of a liquid mixed with at least one of a foam-forming substance and cleaning agents, the container including means for producing a foam layer with the foam layer having filter properties in that the foam layer filters out from a dishwashing liquid passed through the foam layer a substantial fraction of particles entrained with the dishwashing liquid and such filtered-out particles are retained in the foam layer. 
 
     
     
       2. The dishwashing machine according to  claim 1 , wherein the means for producing a flow of a gaseous fluid are disposed in a bottom area of the container. 
     
     
       3. The dishwashing machine according to  claim 1 , wherein the means for producing a flow of a gaseous fluid includes apertures in a bottom sheet of the container. 
     
     
       4. The dishwashing machine according to  claim 1 , further comprising means disposed in an upper area of the container operable to guide dish washing fluid having particles entrained therewith into contact with the foam layer. 
     
     
       5. The dishwashing machine according to according to  claim 1 , wherein the container includes valve means in a bottom area of the container through which both the cleaning dishwashing fluid and the contaminated foam flow away separately. 
     
     
       6. A method for filtering particles from a quantity of liquid in a dishwashing machine, the method comprising: generating a foam layer with the foam layer having filter properties in that the foam layer filters out from a dishwashing liquid passed through the foam layer at least a fraction of particles entrained with the dishwashing liquid; and trickling a dishwashing liquid having particles entrained therewith downwardly through the foam layer, wherein at least a fraction of the particles are retained in the foam layer, while collecting below the foam layer the quantity of dishwashing liquid from which the fraction of particles have been disentrained. 
     
     
       7. The method according to  claim 6  and further comprising removing via suction foam that has been contaminated due to its entrainment of particles. 
     
     
       8. A device for filtering particles from a dishwashing fluid in a dishwashing machine, comprising: a container structured to retain therein a predetermined quantity of liquid mixed with at least one of a foam-forming substance and cleaning agents; a metering device structured to produce a flow of a gaseous fluid through the predetermined quantity of liquid so as to generate a foam layer with the foam layer having filter properties in that the foam layer filters out from a dishwashing liquid passed through the foam layer a substantial fraction of particles entrained with the dish washing liquid and such filtered-out particles are retained in the foam layer; and a turbidity sensor structured to detect a turbidity of the dishwashing liquid, wherein the metering device is further structured to vary the foam layer to match a degree turbidity detected by the turbidity sensor. 
     
     
       9. A method for filtering particles from a quantity of liquid in a dishwashing machine, the method comprising: flowing a gaseous fluid through a predetermined quantity of a liquid mixed with at least one of a foam-forming substance and cleaning agents in a container so as to generate a foam layer with the foam layer having filter properties in that the foam layer filters out from a dishwashing liquid passed through the foam layer at least a fraction of particles entrained with the dishwashing liquid; and trickling a dishwashing liquid having particles entrained therewith downwardly through the foam layer, wherein at least a fraction of the particles are retained in the foam layer, while collecting below the foam layer the quantity of dishwashing liquid from which the fraction of particles have been disentrained; detecting a turbidity of the dish washing liquid; and varying the foam layer to match a degree turbidity detected by the turbidity sensor. 
     
     
       10. The dishwashing machine according to  claim 1 , wherein the means for producing the foam layer produces a flow of a gaseous fluid through the predetermined quantity of the liquid so as to generate the foam layer. 
     
     
       11. The method according to  claim 6 , wherein the foam layer is generated by flowing a gaseous fluid through a predetermined quantity of a liquid mixed with at least one of a foam-forming substance and cleaning agents in a container.